The Gene Expression and Regulation during Odontogenesis (GERO) Program Project grant is a collaborative effort between investigators from the Department of Pediatric Dentistry at The University of Texas Health Science Center at San Antonio, The University of Missouri at Kansas City, and nineteen fellow investigators from eight different domestic and four different foreign institutions. The overall objective of this interdisciplinary, multi-disciplinary research team of scientists is to understand the fundamental multi-disciplinary research team of scientists is to understand the fundamental regulatory mechanisms involved in tooth formation, tooth-specific gene expression, and matrix protein function. The program is composed of three Cores, designed to integrate the four research projects into a coordinated, goal-oriented effort, which is efficiently coordinated for maximum productivity and oversee research activities while providing both internal and external reviews. The Research Core consists of four individual but related research projects to investigate: 1) the role of BMP4 in tooth formation and potential regulation of this cytokine by the transcription factor Msx1; 2) the regulation and function of enamelin, and enamel matrix protein; 3) the regulation and function of dentin sialophosphoprotein (DSPP) during odontogenesis; and 4) the regulation and function of a newly isolated enamel proteinase, enamel matrix serine proteinase 1 during amelogenesis. These research projects will be supported by a Service Core, entitled the "Cell Immortalization and Transfection facility," (CIT) which will provide unique dental cell lines and stable cell transfections for the GERO investigators. While the individual projects all have the potential to produce significant advances related to their research goals, the integrated format of this Program Project grant will further facilitate the productivity, resources, and potential of significant contributions by this highly motivated team of research investigators.